Control mechanism



June 26, 1951 P, L. DE JARLAIS ET AL 8,514

CONTROL MECHANISM 2 Sheets-$heet 1 Filed Jan. 19, 1950 Ha. I

@w m mg m T W WM IEC HM F L M M H? Y B M a June 26, 1951 P. DE JARLAIS ET AL 2,558,514

CONTROL MECHANISM Filed Jan. 19, 1950 2 Sheets-Sheet 2 INVENTORS PH/L/PL. DEL/APLA/S HAZEN C. DRATT BYM MW A T TORNE vs fatented June 26, 1951 UNITED stares rarest "rirics Minn, assignorsto Hoffman Engineering 001- poration, Anoka, Minn, a corporation of Minnesota Application January 19, 1950, Serial No. 139,521

Claims. 1

This invention relates tocontrol mechanisms and more particularly to a mechanism which can be inserted into" a pull type control for disabling the action of said contrcl'at se'lected'intervals under controlof'an electric circuit. In many mechanisms, such as punch presses, shearsiormingpies'ses and the like, the actuation'oi thepress mechanism or other mechanism is "controlled by means of either a foot treadle'or hand l'e'veror some other inechanicallinkage which operates through a pull'link' for the actuationof clutch orpower' control, so as to initiate or stop actuation of the press or mechanism. In applying safetycontrols to such presses and the like, it has been found that disabling of the control, was to stop the op'erati'oi'i of the press or machineunder selected-conditions canb'est be accomplished by inserting mime of the pull linksof the controlling system a device which in effectdisconnects the link so that actuation of thetreadl'e'or lever does no't'iihpose upon the machine aforce suitable for causing actuation. A machine control of this type is disclosed in the prior application of Charles L. Horn an'd'PhilipDeJarlais Serial No. 771088 filed February 18, 1949, for Automatic Safety Guard for 'Powe'r'Presses. In said application actuationof the press is accomplished by rnfeansof a foot treadl'e; which pulls on the clutch control rodof the pressso-as to actuate the press. Safety'controlsare interposed utilizing a device which in'effect disconnects the clutch control rod under certain conditions so that when the foot treadle is actuated the rod no longer exerts apull on the clutch device of themachine and hence the machine does not actuate. This safety device is shown at-85-in Figure'3 of said application.

It is anobl'ect of thepresen't inventionto provide animproved-releasingdevice which is positive in its operation-, stu'rdy, easily manufactured and capable of repeated operation without malfunctioning;

It is a further object of the-invention to provide an improved release mechanism for a machine control.

It is another object. of the invention to provide av magnetically. operated releasemechanism for a control for disabling. said control when the magnetic mechanism is de energized.

It is another object of the invention to provide a releasable pullrod control utilizing a toggle joint capable of beingheld in straight condition by amagnetic mechanism.

Other and furtherobjects of the invention are those inherent: in the apparatus herein illustrated, describedand claimedr The invention is illustrated with reference to the drawings in which corresponding numerals refer to the same parts and in which Figure l is a longitudinal sectional view; partly broken away; illustrating the apparatus of the instant invention;

' Figure 2 is a transverse"longitudinal sectional view taken along the line" and in the direction of arrows 2-2 of Figure 1, it being noted that the sectional view of Figure 1 is taken alongth'e line and in the direction of arrows-l lof Figure-2i Figure 3 is a transverse longitudinal sectional View taken in the opposite'direction as com-pared to Figure 2,'andalon'g the line and in the-direct'i'on of arrows 3'3 of Figure 1;

Figure ris a side'elevational view and illustrates a somewhat modified-formofthe'invention.

Referring to 'thedrawings; Figures 1, 2and-3, which show an illustrative form ofthe invention, at Iii and i i there is shown a pullrod which in'the normal machine, such as a punch press or other mechanism, is a solid rod in which the parts IE and I I are the same pieceof metal. This rod,

"which-may, for example; be a clutch control rod operatedbya treadleat I3; is usually provided with a-clevis at l tthat is adjustable by means ofthe screw-thread It; and nutsiii and ll so as toadj-ust-the-length cfthe pull rod.- Where safety-ccntrols areinstalled on such a press-brother mechanism utilizing such a pull rod control; the safetycontrols-serve to disable the pullrods and in effect serve to disconnect the portion 1 E from theportion-H, so far as transmitting any pull is concernedwhen the safety controls are actuated. In-the instantinvention, one form of which is illustratedin- Figures l-3, the portion IQ of the rodand the portion H are adapted to be held immovable with respect to each other, so that a pull exerted on Hi will be transferred to rod ll when anelectromagnet generally designated 20 is energized and are adapted to be in effect disconnected when the electromagnet 2B is de-energized. The apparatus for accomplishing this function is as follows:

A framework consisting of a case having edge plates 2l22 and side walls 23 and 24, together with a top edge plate 25, is assembled and held together by corner blocks 26, the walls being held to theblocks by suitable screws and bolts. The case thus formed is closed at all-sides; except along the bottom; as at 2?, and serves as an enclosure and framework in which most of the remaining mechanism is housed. Between the lower edges of the face plates 23 and 24 thereis mounted a block 28 which is screw threaded at 29 to receive the screw threaded end of rod I9. The block 28 is held in place by suitable cap screws at 30. This connection thus firmly attaches the entire case to the upper end of the rod I8 and hence as the rod l is pulled downwardly in the direction of arrow 32, the case which is generally designated 34 is likewise pulled downwardly, and when the rod l0 moves upward opposite to the arrow 32, the case 34 likewise moves upwardly. Normally, there is a spring under or attached to treadle l3 which moves it upwardly and this likewise pushes the rod l8 up.

Within the case there is mounted a toggle composed of a pair of links 35 which act in unison and a pair of links 36 which act in unison. The pair of links 36 are pivoted upon the shaft 31 which is passed through holes 38 in the side plate 23 and hole 39 in the side plate 24. Outside of the side plates the shaft 31 has the reduced diameter as at 48 and 4|, and on these reduced ends there are mounted spacing washers and then the connecting links 42 and 43, each of which has a vertical slot therein as at 44 for the link 42 and at 45 for the link 43. The slots 44 and 45 are just slightly larger than the diameters of portions 40 and 4| of the pivot pin 3'1, and hence the links 42 and 43 are free to slide on the portions 40 and 4|, being held thereon by the outside washers 46 and 4'! which are in turn held in place by wire ring keys at 48 and 49.

The two toggle links 35, which act in unison, are mounted upon a pin 50 that is provided with reduced portions at 52 and 53. These reduced portions extend through a pair of slots 54 in the plate 23 and 55 in the plate 24, these slots being likewise just slightly larger than the diameter of the two reduced portions 52 and 53 of the pin 58, and accordingly the pin 58 is free to move vertically in the slots 54 and 55 in the side plates. Outside the side plates 23 and 24 there are placed spacing washers as at 56 and 51, and outside these the reduced ends 52 and 53 of the pin 60 extend through holes in the lower ends of the links 42 and 43. Thus, the reduced portion 52 of the pin 50 extends through the hole 58 in the link 42 and is held thereon by means of the Washer 60 which is in turn held in place by means of the snap ring key 62. Likewise, outside the washer 51 the reduced end 53 of the pin 58 extends through the hole 59 in the lower end of link 43 and is held in place by the washer 6|, which is in turn held in place by the snap ring key 63.

The two sets of toggle links 35 and 36 are attached together by means of a toggle pin at 66, which extend not only through the toggle links but also through a pair of supporting plates 61 and 58. The plates and 68 are held spaced apart by means of a short length of tubing as at 69 and the pin 66 thus passes through the plates 61 and 68 and thence through the washers at 18 and 1|, thence through apertures in the lower ends of the toggle links 63, thence through washers at 12 and 13, thence through apertures in the upper ends of the links 35 and the ends of the pin 66 are held in place by means of snap ring keys at 14 and 15. The spacing plates 61 and 68, which serve to carry the armature 16 of the electromagnetic unit 20, are also attached to the toggle links 36 by means of a pin at 11, there being likewise a spacing tube at 18, spacing washers at 19 and 80 and retaining washers and snap ring keys at 8| and 82. The plates 61 and 68 hence act in concert and move along with the two toggle links 36 which likewise act in concert. If desired, the two links 36 and plates could have the plates 61 and 68, respectively, formed integrally therewith.

Between the plates there are a plurality of laminations forming the movable armature 16 of the electromagnetic unit 29, these laminations being held in place by a pair of rivets at 83-83. The electromagnetic unit also includes a stationary magnetic core at 85 which is mounted between the side plates 23 and 24 by means of bolts at 86. Upon the central leg 81 of the electromagnetic path there is a winding at 88 which is served by lines 89. Whenever the lines 89 are energized, this energizes the coil 88 and hence the electromagnetic unit 85 attracts the armature l6 and holds it in place, providing it is already adjacent the electromagnetic circuit 85. Shading coils are provided at 999|l to reduce chatter where the winding 88 is energized with alternating current.

In addition, there is provided at 9| a spring which is attached by means of rivets 92 to the side plate 23. This spring extends over between the polepieces of the electromagnetic circuit in a position such that when undefiected it is in the dotted line position as shown at 94. It is in a position to be engaged by the central area 95 of the armature 16 when the latter is adjacent the magnetic circuit 85, and when the magnetic circuit is energized, the armature 16 pulls against the polepieces and depresses the spring 9| to the position shown in full lines at 96. The spring serves to kick the armature 16 away from the polepieces when the magnetic unit 28 is de-energized and hence throws the toggle out of a straight line position, thus initiating motion in a direction to break or fold the toggle.

The upper portion of the slide links 42 and 43 are attached together by means of the bridging block 98 which is held to the links by means of cap screws 9999. The bridging block is threaded at 91 to receive the lower end of the pull rod ll.

Ihe operation of the device is as follows: In normal operation the two links IE! and II when not under any operative pulling force are in the position as shown in the full lines, and circuit 89 is energized. Under such conditions the toggle links 3535 and 3'636 are in the full line position of Figure 1, which brings the armature 16 into contact with the polepieces of the magnetic circuit 85 of the unit 28, with force sufficient to compress the spring 9| from the dotted line to the full line position. If in this condition the treadle I3 is depressed, force is transmitted to rod Thus, in this position the magnet 29 firmly retains the armature l6 and if then a pull is asserted on rod I8, the toggle in the straight position and held magnetically is not broken to the dotted line position, and hence the force of the rod I0 is transmitted through the side plates 23 and 24 to the upper toggle pin 37, and thence down through the links 36-35, pin 69 and toggle links 3535 to the pin 59, and hence has a pulling force through the side links 42 and 43 to the connector 98 and hence to the rod |l. Accordingly, when the magnetic device 29 is energized and a pull is placed upon the rod IE], it is transmitted through the entire device t. the rod and the two rods I0 and I are, therefore, effectively coupled together so as to perform their controlling function.

However, if circuit 89 should be de-energized, as might occur when one of the safety devices controlling the press became actuated, and if under the same conditions, with the circuit 89 thus de-energized, the operator pushed on treadle l3 5 and hence puns down on the rod' Io thiswould cause the entire case to move downwardly, or relatively speaking, the rod II would'pull upwardly, and in so doing causes the slide links 42 and 43 to move from the full line position to the dotted line position. When thisoccurs, pivot pin 50 attached to the toggle is raised in the slots 5455 and causes the toggle links 35 to be liita. to the dotted line position of Figure 1, likewise causing the toggle links 36 to be movedto th' dotted line position, which also carriesthe armature lfi'to the dotted line position well away from the magnetic circuit of the'device' 20. Accordingly, when the magnetic device 20- is not energized, a pulling force in the direction of'arrov 32 on rod I and while rod H remains stationar, causes the toggle links to be broken to the-dot ted line position, and hence the pulling force on the rod is not transmitte'dfrom rod I0 to rod i and hence-any mechanism controlled thereby it not in effect operated.

In the form of invention illustrated in Figure 4 the operator-actuated member of the controlling device is in the form of a lever I00 pivotedat' I01 so that it can be moved by the operator when force is applied in the direction of arrow I02" on the treadle portion I03. The lever I00 has upstanding portion at I04 extending over at I05 and provided with a pivot at I06. The cooperating portion of the controlling mechanism (which for controlling action is moved by. the foot treadle or lever E00) is shown at I01 and is likewise in the form of a lever pivoted at I08. The lever i has a portion I09 extending downwardly anthence towards the portion I04 at the bent portion H6, the latter having a pivot at H I. Th lever I01 serves to perform the controlling func tion which may be by virtue of rotation of-pivot I08 or can, if desired, be accomplished by means of a pull rod at I I4 which is pivotally at tached to the levger I01 by means of the pivot I I5.

If the mechanism of which the controlling apparatus forms a part does not inherently include a stop for the motion of lever I01 (or pull rod I where used) a stop is provided at I I3. Likewise if the mechanism of the apparatus to which the controlling device is attached, does not normal exert a force in the direction of arrow I I6 on lever I01, the spring II1, which is attached to th frame I I8, is hooked onto the lever I01 so as nor mally to hold it in the position shown in ure 4.

To the pivots I06 and I I I there is attached the free end of a toggle generally designated I com posed of the link I2I and the link I22, these links being pivoted together at the common pivot I23. An armature I24 is attached to one or the other of the levers I2! or I22 and is positioned so as to cooperate with the polepieces I26 of the electromagnetic device I21 which is served by the circuit composed of the wires I28.

When the wires I28 are energized the electromagnetic device I21 attracts the armature I24 to it solidly, thus holding the toggle I2II22 in the nearly straight condition. Accordingly, if under such conditions the operator presses a foot on treadle I03 the pivot I06 is moved downwardly in the direction of arrow I30 and in so doing ini poses a force upon the toggle I20 which therefore exerts a force in the direction of arrow I3I upon the pivot III, thus causing the portion III) of lever I01 to be pushed downwardly to effect the controlling operation. A small spring I34 may be provided between the portion I09 of the lever I01 and the toggle I20 so as to urge it normally towards the broken position shown in dotted lines of- Figure 4.- However, the spring I34 is very light and is capable of being overcome by thrforce exerted by the electromagnet I21 upon the armature I24. The'spring I34 assists in opening the toggle I20.

In the-event circuit I23 is not energized, electromagnet I21, therefore, does not exert forceon the armature I24. Accordingly, if under such conditions the operator exerts force in the direction of arrow I02 upon the treadle I03, the force downwardly at pivot I06 canot be transmitted by the toggle I 20 andit accordingly assumes the position shown in dotted lines in Figure 4. It will be appreciated that under the conditionsjust described, the lever I01 is'not moved;

As many apparently widely different embodiments of this invention may be made without departing from the spirit and scope thereof, it is to be'understood that we do not limit ourselves to the specific embodiments herein.

What we claim is:

1; In a controller mechanism, a movable operator actuated device having a normal position and having a first pivot thereon, a movable control member having a normal position and having a second pivot thereon adapted to be moved by said device, said first pivot being movable as a part of said device toward the second pivot when said device is operator actuated from its normal position for controlling movement, a toggle composed of a pair of link means, pivoted together by common pivot means, each link means having a free end, said free-ends being pivoted on the first and second pivot, said toggle being in a. nearly straight condition when the device and member are in their normal positions and movable from said position to a broken position when the device is moved in control effecting direction and said member is not moved, a stop for holding said toggle from assuming an over-center position when the device and member are in their normal positions, and electromagnetic means having an electric circuit connected thereto connected to said toggle for holding said toggle in a substantially straight force transmitting position when the circuit is energized.

2. The apparatus of claim 1 further characterized in that means is provided for biasing said device in a direction opposite to the direction it is moved for effecting control for straightening the toggle.

3. The apparatus of claim 1 further characterized in that bias means is provided for urging said toggle slightly towards broken position, the force of said bias means being so small that it is capable of being overcome by the holding effect of theelectromagnetic means when the latter is energized.

4. A device for effectively connecting and disconnecting a force imparting member and a member adapted to be moved thereby in a mechanical control, said members being positioned so as to present a space therebetween comprising a toggle composed of first and second links each having a free end and a comon end, said common ends of said links being pivoted together for movement to and from approximately straight and broken positions, said toggle when in approximately straight condition extending across said space between said members with the free end of said first toggle link nearest the force-imparting member and the free end of said second toggle link nearest the moved member, first pivot means connecting the free end of the first toggle link to the force imparting member and second pivot means connecting the free end of the second toggle link to the moved member, the axes of said first and second pivot means being restrained to movement in substantially the same plane, and electromagnetic means including an electric circuit for maintaining said toggle in said approximately straight condition when said circuit is energized for transferring force therethrough.

5. The apparatus of claim 4 further characterized in that spaced plates having parallel slots therein are provided for maintaining the first and second pivot means in substantially the same plane of movement.

6. An actuator having a bifurcated end composed of spaced portions, a first pivot extending across said portions, a member having a bifurcated end composed of spaced parts having a second pivot thereon, said pivots being held relative to each other so as to be movable in substantially a common plane, with the first pivot between said member and second pivot and said second pivot between said actuator and first pivot, said pivots being substantially parallel, a toggle composed of first and second links pivoted together at a common pivot, each link having a free end, said free ends being pivoted on the first and second pivots, and an electromagnetic device having acontrolling circuit attached to said toggle for maintaining it in a substantially straight condition when the circuit is energized.

7. The apparatus of claim 6 further characterized in that said first pivot extends into slots in said parts and said second pivot extends into slots in said portions.

8. The apparatus of claim 6 further characterized in that said parts are in the form of plates substantially enclosing the toggle, pivots and electromagnetic means.

9. The apparatus of claim 4 further characterized in that the force-imparting member is a first lever having a portion to which said pivot means is attached and said member adapted to be moved is a second lever to which said second pivot is attached, and said electromagnetic means is mounted on one of said levers in a position such that when the electromagnet is energized it will hold the toggle in said approximately straight position.

10. In a controller mechanism comprising a manually operable lever having a substantially vertical portion and a portion extending therefrom so as to form a mounting for a first pivot, a toggle comprising a pair of links pivotally connected together with the free upper end of one of said links connected to said first pivot, an actuated member comprising a horizontal lever pivoted at one end thereof, said actuated member having a portion forming a second pivot means to which the lower free end of the other link of said toggle is connected, electromagnetic means mounted upon one of said levers in a position such that when energized it will attract and maintain said toggle in an almost straight line position.

PHILIP L. DE JARLAIS.

HAZEN C. PRATT.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 784,717 Walle Mar. 14, 1905 925,673 Zook June 22, 1909 2,280,246 McCullough Apr. 21, 1942 Certificate of Correction Patent N 0. 2,558,514 June 26, 1951 PHILIP L. DE JARLAIS ET AL.

It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows:

Column 5, line 19, after rod, third occurrence, for the indistinct numeral read 11; line 33, after lever, second occurrence, for the indistinct numeral read 107 line 41, for levger read Zeoer; line 44, after rod for the indistinct numeral read 114; column 8, line 3, after said insert first;

and that the said. Letters Patent should be read as corrected above, so that the same may conform to the record of the case in the Patent Oflice. Signed and sealed this 18th day of September, A. D. 1951.

THOMAS F. MURPHY,

Assistant Gammz'ssz'oner of Patents. 

